12-22201987-A-T

Variant names:

• chr12-22201987-A-T
• rs704219
• NM_003034.4:c.636T>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_003034.4(ST8SIA1):​c.636T>A​(p.Ile212Ile) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: ST8SIA1 NM_003034.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.375
• Publications: 16 publications found

Genes affected

ST8SIA1 (HGNC:10869): (ST8 alpha-N-acetyl-neuraminide alpha-2,8-sialyltransferase 1) Gangliosides are membrane-bound glycosphingolipids containing sialic acid. Ganglioside GD3 is known to be important for cell adhesion and growth of cultured malignant cells. The protein encoded by this gene is a type II membrane protein that catalyzes the transfer of sialic acid from CMP-sialic acid to GM3 to produce gangliosides GD3 and GT3. The encoded protein may be found in the Golgi apparatus and is a member of glycosyltransferase family 29. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jan 2015]

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.51).
• BP7: Synonymous conserved (PhyloP=0.375 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_003034.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ST8SIA1	NM_003034.4	MANE Select	c.636T>A	p.Ile212Ile	synonymous	Exon 5 of 5	NP_003025.1	Q92185-1
	ST8SIA1	NM_001304450.2		c.207T>A	p.Ile69Ile	synonymous	Exon 4 of 4	NP_001291379.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ST8SIA1	ENST00000396037.9	TSL:1 MANE Select	c.636T>A	p.Ile212Ile	synonymous	Exon 5 of 5	ENSP00000379353.3	Q92185-1
	ST8SIA1	ENST00000261197.7	TSL:1	n.*118T>A		non_coding_transcript_exon	Exon 4 of 4	ENSP00000261197.3	Q92185-2
	ST8SIA1	ENST00000261197.7	TSL:1	n.*118T>A		3_prime_UTR	Exon 4 of 4	ENSP00000261197.3	Q92185-2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1461222 Hom.: 0 Cov.: 45 AF XY: 0.00 AC XY: 0 AN XY: 726898

African (AFR) AF: 0.00 AC: 0 AN: 33436

American (AMR) AF: 0.00 AC: 0 AN: 44632

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26104

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86148

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53340

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111744

Other (OTH) AF: 0.00 AC: 0 AN: 60368

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 193827

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.51
CADD	Benign	5.5
DANN	Benign	0.74
PhyloP100		0.38

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs704219; hg19: chr12-22354921;